Pulsations of gamma rays detected from pulsar J0952-0607

An international team of astronomers reports detection of gamma pulses from the millisecond pulsar (MSP) known as PSR J0952-0607. The discovery, available in an article published on May 27 on arXiv.org, sheds more light on the properties of this pulsar and could be helpful in improving our understanding of PSM in general.

Pulsars are highly magnetized rotating neutron stars emitting beams of electromagnetic radiation. Pulsars with the fastest rotation, with rotation periods of less than 30 milliseconds, are called millisecond pulsars. It is assumed that the MSPs are formed in binary systems when the initially most massive component is transformed into a neutron star which is then generated by the accumulation of secondary star matter.

A class of extreme binary pulsars with semi-degenerate companion stars is called "spider pulsars". These objects are further classified in the category "black widows" if the companion has an extremely low mass (less than 0.1 solar mass), while if the secondary star is heavier, they are called "redbacks" .

Discovered in 2017, the PSR J0952-0607 is one of those black widows. It is an MSP binary radio with a spin frequency of 707 Hz, making it the known pulsar that turns the fastest outside a globular group. The companion star of the system has a mass of about 0.02 solar mass and an orbital period of about 6.42 hours.

PSR J0952-0607 is very low in gamma rays and many of its parameters remain unknown. That is why a group of astronomers led by Lars Nieder of the Max Planck Institute for Gravitational Physics of Hanover, Germany, decided to conduct a very sensitive search for gamma-ray pulsations in this pulsar , mainly from the data analysis of Fermi, NASA. spatialship.

Although the demanding investigation required a new research technique and more sensitive timing methods, it was successful. In addition to the detection of gamma pulsations, the study also made it possible to determine certain parameters of the pulsar with great accuracy.

"Using a sensitive and fully consistent pulse search technique, we detected gamma ray pulsations from the PSR radio pulsar J0952-0607 when searching around parameters reported by Bassa et al. (2017b)" , wrote the researchers.

According to the study, the gamma ray pulse profile of the PSR J0952-0607 shows two separate peaks of about 0.2 rotation. In addition, the phase shift between the gamma ray profile and that of the radio pulses seems to be around 0.15. These two values ​​are typical for MSPs.

Research has shown that the PSR reduction rate J0952-0607 was approximately less than 4.6 zeptosends per second. This makes it the fastest pulsar for which this parameter has been reliably constrained.

Furtmermore moreover, astronomers have calculated that the brightness of PSR J0952-0607 in the deceleration is about 64 decillions erg / s. They also found that the strength of its surface magnetic field is relatively small, not exceeding 82 million G, which ranks it among the 10 lowest of all pulsars discovered to date.

Despite the efforts of the team, some PSR parameters J0952-0607 are still unknown. Further study of this pulsar using Fermi and the LOFAR (Low-Frequency Array) radio telescope could prove very useful in resolving many of the remaining uncertainties.

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